The invention relates generally to wood or brush chipping machines and, more specifically, to a mechanism and method for automatically controlling the feeding of wood or brush into the machine to ensure efficient chipping.
Wood and brush chippers of the type having a rotating chipping disk and a pair of coacting feed rolls for feeding the wood or brush into the chipping disk are well known. One such device is described in U.S. Pat. No. 4,442,877. The chipping efficiency of such machines depends on the maintenance of a high rotational speed of the chipping disk and on the "bite" or kerf that the chipping disk removes from the infeeding wood or brush. Efficiency is reduced if the speed of the chipping disk is reduced due to lugging of the drive engine of the chipper disk or if the wood or brush is not aggressively moved into the chipping disk so that frictional rubbing and burning of the wood or brush occurs rather than the removal of material by chipping. Manual intervention by the operator is required to interrupt the feed rolls to avoid killing the engine of the chipping machine and to allow the engine to return to an efficient chipping speed.
The present invention automatically interrupts the rotation of the feed rolls in response to low engine rpm so that engine horsepower is maintained at an efficient level and so that continual manual attention is not necessary and to free the operator for gathering and feeding of material into the chipping machine.